1. The first duty of a state is to defend (militarily?) its citizens. — John Davis

They first duty of a state should be provide employment and food to their citizens.

I'm not aware of anything explicitly about this, but this is generally how citizenship in Greek city states worked. The polis' most important function was organizing common defense and a system of laws for adjudicating disputes and property rights.

This obviously shifted over time though. Athens during its "golden age" was using a significant portion of its annual income on public works and art. There were also social services including medicine provided for the poor in many Greek states.

I don't know how much the idea really equates to other areas. The Greeks, and later Rome had a key distinction between citizens and free foreigners living in their lands, or slaves.

For a lot of history civilizations essentially just defined citizenship as living in area controlled by a given monarch.

Certainly medieval thought framed the responsibilities of the state and citizens far more in religious terms and appeals to natural law vis-a-vis God's will than appeals to citizenship as a concept.

CTvI. Thank you for an informative contribution.

They first duty of a state should be provide employment and food to their citizens. — javi2541997

Where is the state going to get the resources to provide employment and food for its citizens?

Of course it has no basis is historical authority. It is a normative statement the kind of which citizenship classes seem to love so much. It is actually rather militaristic. There is some sort of a legal basis for it though. In international law state sovereignty is recognized if it is able to defend its borders. (I belief, but I am jo expert).

Where is the state going to get the resources to provide employment and food for its citizen — synthesis

From the revenue of the tax income. Thus, citizens effort to maintain the state. But the revenue obtained shouldn’t be invest in military services I guess

The first duty of a state.... The second duty of a state.... — John Davis

Probably best to start with a clear statement of what you think a (the) state is. And I am pretty sure that answer might vary around the world, whatever lip-service some might pay to certain ideals. In the US it's "We the people...". In other western countries I am not sure what it would be. But it seems to me for this thread we need at least a starting point, even if in our collective genius we move away from and refine and correct it.